Brake for car-wheels.



vthe drawings, is a specification. v

My invention which relates to thatclass of brakes UNITED sTATEs PATENT OFFICE.'

JOHN H. SHAW, OF NEW HAVEN, CONNECTICUT.

:snm Fon cnn-mans.

Specification of Letters Iatent.

Patented Aug'. 27, '1907.A

Application filed December 14, 1906. -Serial No. 547,85.

comprising' a holder and a detachable or renewable brake shoehas for its object the production of a shoe which will remain operative in case it is broken;v and has attaching devices which will give the shoe or the parts of theshoe, ii broken, a rocking bearing in the holder with reference to the braking surface of the wheel, and `prevent lateral movement'of the shoe or parts of the shoe in the holder, and which will accomplish these results by a simple vand cheap construction oi the parts, and to these and other ends consists in the various improvements and combinations of parts set forth 'and claimed hereinafter.

, In the drawings, Figure l represents a perspective view of the shoe alone, Fig. 2, a similar view of the holder alone, Fig. 3, a similar view of the shoe and holder together, Fig. 4, another view, in perspective,

ofthe holder, Fig. 5, a cross section of the holder and- 'formed in and extending across the front face 4of the holder, their openings into said face being narrower than `the width of said recesses inside oi the openings. A slot D extends from end to end of the holder, the longitudinal plane of said slot passing through said recesses C. y l

E designates the body .or the brake shoe, and F, a

plurality oi transverse projections cast Vupon and ex 'tending across the back 'of the brake' shoe corresponding in position and in cross section to the position and shape of the recesses C in the holder A. Slots Gr are cast in the projections F, so that when the parts are ,assembled these slots will come into the `longitudinalV plane of the slotl D in the holder.

A metallic strap H shaped to conform to the curvature of the brake shoe and holder is provided, so that when the same are assembled it will pass through the slot D in the holder, and throughfthe slots G in the projections F. One end Loi then strap H is turned to form a stop, and the other end is provided'with a hole K for a cotter pin (not shown).

l The Vbrake shoe and holder are assembled by sliding the projections F laterally @pto the rec C, said' projections and recesses dovetailing loosely into each other to lock the shoe and holder together. The strap H is then passed4 through the slot in the holder A, and

through the slots-in the projections of the brake shoe,

and thus prevents lateral movement of 'the slioe in, theholder. The strap is secured in place by a cotter pill.

The projeptions F are .preferably rounded on ,the

back, as'shown, so that when the parts are assembled, the rounded projections onftheA back of the brake shoe bear upon the body ofthe holder in the bottom ofthe recesses, and said projections fi't loosely in said recesses, so as to permit a rocking motion of the shoe on one or another of the projections F, enabling the brake shoe to' accommodate itself to the surface of the wheel.

The principal object of providing a plurality of transverse recesses in the holder. and transverse projections 'i'n the shoe is to provide for the continued efficiency ol' the brake after the shoe is broken, Which'must ultimately happen as the shoe wears thin or is subjected to a breaking strain.

j Nicks L are'provided between each oi the projections F on the shoe, so that snoes so constructed will break transversely on these lines between the projections'F, and each portion oi the shoe then remains seated on its own rocking bearing. A portion of a shoe so broken is shown in Fig. 7. The efficiency of the shoe remains unimpaired, and further breaking is practically eliminated, because each portion of the shoe is then at liberty to accommodate itself indedendently to the surface of thecar wheel. Lateral displacement of the brake shoe, or of rthe parts oi the shoe, when broken, with respect to the holder is lprevented by the strap H passing through the slots D and G. As the eiiciency oi the brake shoe when so constructed and combined with the holder is not impaired by any ordinary raetul e, it may be u'sed until worn down very thin, and may then be easily replaced or renewed. A

The construction of the parts is simple, and the r shoe and holder may be formed by casting without any necessity for finishing or fitting, because the construction is such that looseness of lit is consistent with the 'shoe being firmly retained in its operative position. Having now described my invention, what I claim and desire to secure by Letters Patent, is:-

1. In a car brake, the combination with a holder, .pro-

vided wlth a plurality of transverse recesses; of a shoe provided with a plurality of corresponding transverse projections on the back thereof adapted to fit loosely in said y recesses in the holder and bearing against the bottom; of said recesses; and means for retaining said projectionsin said recesses, substantially as and for the purposes described.

2., In a car brake, the combination with va'holder, provided 'with :1 plurality of transverse recesses; 0f a shoe provided \vith a plurality ot' corresponding transverse projeutions on the back thereof adapted to (it in said recesses in the holder, said shoe being adapted .when broken to form a series of-shoes, each having,r one of said projections, substantially as and foithe purposes described.

3. In acar brake, the combination with a holder, provided with a plurality of transverse recesses; of a shoe provided with a plurality of corresponding transverse projections o n the back thereof adapted to fit in said recesses vstnntinlly as and for the purp ses described.

In witness whereof, I have hereunto set my hand ou the 10th day of December, 1906.

JOHN H. SHAW.

Witnesses M. OLivn WILLIAMs, SAMUEL H. Flsxmk. 

